Add sync error logging, extend error flash, fix unload saves

- Log workforce sync errors to backend stdout so they appear in docker logs
- Extend error flash from 5s to 15s so errors are readable
- Replace sendBeacon (POST-only) with keepalive fetch (PUT) on unload —
  sendBeacon was hitting 404s on all three unload saves

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/node_modules/@remix-run/router/package.json

@@ -0,0 +1,33 @@
+{
+  "name": "@remix-run/router",
+  "version": "1.23.3",
+  "description": "Nested/Data-driven/Framework-agnostic Routing",
+  "keywords": [
+    "remix",
+    "router",
+    "location"
+  ],
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/remix-run/react-router",
+    "directory": "packages/router"
+  },
+  "license": "MIT",
+  "author": "Remix Software <hello@remix.run>",
+  "sideEffects": false,
+  "main": "./dist/router.cjs.js",
+  "unpkg": "./dist/router.umd.min.js",
+  "module": "./dist/router.js",
+  "types": "./dist/index.d.ts",
+  "files": [
+    "dist/",
+    "*.ts",
+    "CHANGELOG.md"
+  ],
+  "engines": {
+    "node": ">=14.0.0"
+  },
+  "publishConfig": {
+    "access": "public"
+  }
+}